434 OF THE SECOND OF JANUARY, 1806. 



belonging to the Jesuits was thrown down, as was also the upper part of the 

 high tower of the cathedral. This part had been but newly built, in order to 

 place a clock thereon, when the earthquake of October, 1864, hurled it thirty- 

 yards distant towards the market-house ; the reconstruction was resumed, and 

 on the day when the clock was placed in position the earthquake again de- 

 molished the dome of the tower, but without injury to the clock. 



From Orizava a valley stretches to the southwest, bordered by steep rocks, 

 through which passes the highway leading to Mexico. In this valley, which is 

 twelve miles long, the concussions were peculiarly violent. Several churches 

 and many private houses were destroyed, and a number of persons lost their 

 lives. Further to the south the towns of Tehuacan and Oajaca were visited 

 most severely ; in the latter five churches were wholly or in part demolished. 

 From the report of a traveller the force of the shocks, in the long distance from 

 Orizava to Oajaca, was peculiar, the effects being rather extended in length than 

 diffused in breadth. The neighborhood of the calcareous mountains, which ri\n 

 parallel to the great chain of the Andes, would seem to have determined the con 

 ditions of the concussions. 



Northward from the peak of Orizava, it was only quite near that point that 

 the movement was violent ; here a church was destroyed. Iti Jalapa, though 

 very perceptible, the phenomenon was attended with no damage. The same was 

 the case to the east, as, for instance, at Vera Cruz. A strong norther was blow- 

 ing at the time, on which account the effects were not perceived on board the 

 ships in the harbor. 



To the westward the oscillations were slighter according to the greater distance 

 from the peak of Orizava. In Puebla the concussions were strong, but not so 

 much so that large buildings were injured. In the city of Mexico the effects 

 were mitigated. According to a communication from a point seventy-two miles 

 west of the latter city, an earthquake, but of no considerable force, was distin- 

 guishable. 



All opinions concur in assigning the peak of Orizava as the focus of the phe- 

 nomenon, as it was also in October, 1864, and it would not be surprising if that 

 mountain, after a repose of three hundred years, should again commence its erup- 

 tions. 



Note. — The following supplementary communication was received from Dr. 

 Sartorius, in a letter of the 27th May, 1866 : 



" We had another earthquake at 9.15 a. m. of May 10, 1866, extending from 

 the peak of Orizava in a direction from southwest to northeast. There were 

 three shocks, at intervals of ten seconds, the last the most severe, followed by 

 continvied tremblings ; the duration of the whole was seventy seconds, during 

 which the barometer fell one-hundredth of an inch, returning immediately after 

 to its original condition. The magnetic needle was without declination, but with 

 a strong inclination north. The earthquake was local, only feeble traces having 

 been observed in the city of Mexico. The shock was so severe in Orizava that 

 several houses were destroyed and some persons killed. The oscillations were 

 from north to south ; the time the same. 



" On the 27 th of April a violent shock was noticed southwest of the city of 

 Mexico, proceeding from the volcano of Jorullo, of which no traces were observed 

 here." 



